78669629 has 4 divisors (see below), whose sum is σ = 78687900. Its totient is φ = 78651360.

The previous prime is 78669623. The next prime is 78669673. The reversal of 78669629 is 92696687.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 36120100 + 42549529 = 6010^2 + 6523^2 .

It is a cyclic number.

It is not a de Polignac number, because 78669629 - 2²⁰ = 77621053 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (78669623) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1289 + ... + 12609.

It is an arithmetic number, because the mean of its divisors is an integer number (19671975).

Almost surely, 2^78669629 is an apocalyptic number.

It is an amenable number.

78669629 is a deficient number, since it is larger than the sum of its proper divisors (18271).

78669629 is a wasteful number, since it uses less digits than its factorization.

78669629 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 18270.

The product of its digits is 1959552, while the sum is 53.

The square root of 78669629 is about 8869.5901258175. The cubic root of 78669629 is about 428.4850765017.

The spelling of 78669629 in words is "seventy-eight million, six hundred sixty-nine thousand, six hundred twenty-nine".